Gong Gong says

This is a posthumous blog of our father's (Lim Kok Ann) life. When our father passed away on 8 March 2003, he left behind an unpublished autobiography. We'd like to celebrate his life by sharing his autobiography through this blog.

"I have dredged these anecdotes from memory just to pass the time; if they amuse my grandchildren their purpose will have been served; if they provide any instruction, it will be a happy coincidence; that they are disjointed is probably to be expected.

Aurora was the name of my grandfather’s house in Kulangsu.   Amoy, where I spent the first five or six years of my life.   I still have vivid memories of events that took place when I was barely three years old.

Lim Kok Ann
October 1996"

Saturday, December 13, 2008

3:18 Joe Melnick and Sabin

The great thing I learned from Joe Melnick was objectivity. He never took anything for granted and weighed carefully any scientific judgement even from the highest authorities. “Show me,” he would say, “don’t just tell me.” He had a confrontation with Dr. Albert Sabin, the inventor of live oral polio vaccine, when Sabin claimed that the vaccine viruses did not attack nerve cells and were not able to cause paralysis in monkeys even when injected directly into the spinal cord, a procedure considered the most testing for neuropathogenicity.
Melnick repeated Sabin’s experiments and confirmed that the monkeys did not develop paralysis, but he found that their spinal cord and brain cells showed signs of virus invasion. To Melnick this meant that the vaccine virus still retained its affinity for nerve cells even if the monkeys did not have paralysis. Perhaps, he argued, the search for a vaccine virus without affinity for nerve cells should be continued. Sabin had to admit that the vaccine virus retained some neuropathogenicity, but the health authorities continued with small trials of oral poliovaccine in the hope that failure of the vaccine virus to cause paralysis in monkeys really indicated that the vaccine virus was not neuropathogenic in humans.

Melnick was not against this, for he accepted that practical tests of the vaccine where it was going to be used was the final arbiter. When the Singapore government debated in 1962 whether Singapore should adopt the Sabin oral vaccine to protect all children against polio, some doctors questioned whether Singapore children should be used as experimental guinea-pigs, so to speak, when the vaccine was not of proven safety. Melnick said to me,“Ann, Singapore is already in the oral vaccine safety experiment. You can choose to be in the group of guinea-pigs that are given the vaccine or you can chose to be in the group of guinea-pigs that are not. After a few years we shall compare the number of polio cases in the first group of guinea-pigs and in the second group. If polio cases in the first group are significantly fewer than in the second, then the vaccine will have been proven to be safe and effective. Otherwise, not.”

In the event, the Singapore experiment proved to be successful in reducing the incidence of paralytic polio in Singapore to less than two annually and no child given the full initial course of Sabin vaccine ever contracted polio.
In Houston I shared an apartment with two of Melnick’s PhD students. One was Dan Turshack from Philadelphia and the other Arwind Diwan from India. Dan gave me an insight into the American way of studying. He had a reading list as long as his arm; once a week the PhD students had to present a seminar on a virology topic in which one of them had to review a journal article and discuss the significance of the new knowledge reported. Everyone was expected to join in the discussion and draw upon their own reading of the literature. “I have time to read everything once only,” Dan told me, “so I have to read for retention.” This was a new concept for me. I had taken for granted that one remembered what one has read, but Dan’s notion of retention was to be able to cite the authors and the date and journal reference of the report and to quote passages verbatim. It was something that I did not know how to do.


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